Medicine: Mysteries of Curare

The conquistadors had no sooner begun cutting their way through the
jungles of South America than they found themselves suffering
casualties from Indian darts tipped with a potent, paralyzing poison.
But a century passed before Sir Walter Raleigh in 1595 carried to
Europe the first samples of "urari"a variant of curare. Years later
botanists classified the shrubs from which curare is made,* and the
brilliant French physiologist, Claude Bernard, in 1856 made an
important discovery: from samples supplied by Brazil's Emperor Pedro II
he showed that curare paralyzes its victims by blocking transmission...